NSK: world’s first bearing line-up to feature a bioplastic cage


Following its development in 2021 of the world’s first bioplastic cage for rolling bearings, NSK can now reveal its initial product line-up. The new heat-resistant cage will be available on its 60 and 62 series of deep groove ball bearings, which are ideal for fan motors in air conditioners. Moving forward, NSK will continue expanding its product portfolio and the associated range of applications for OEMs looking to develop environmentally friendly products.

NSK’s 60 and 62 series deep groove ball bearings feature the new environmentally friendly, heat-resistant bioplastic cage (photo NSK)

By manufacturing the bearing cage from a bioplastic material – which derives from renewable biomass sources (mainly plants) – it is possible to reduce lifecycle CO2 emissions by 91% in comparison with conventional plastics made from fossil fuels, thus contributing to carbon-neutral initiatives. As a point of note, conventional bioplastic components have suffered from low heat resistance, but tests show that the cage material selected by NSK can withstand operating temperatures of up 120°C. Using CAE technology in the development process allowed NSK to evaluate dimensions, shape and deformation, and verify the suitability of existing mould tools. The company could also assess important attributes such as strength and quality. In particular, NSK used digital twin simulation to evaluate cage stress characteristics under operating conditions. Accelerated by simulation results, NSK conducted further validation of cage performance during rotation via the real-world testing of physical prototypes. By applying the two perspectives in parallel, the company reduced cage development time to one-third of that of conventional processes.

NSK’s bioplastic cage (photo NSK)

Besides, NSK’s functional evaluation tests confirmed that bearings featuring the bioplastic cage have an equivalent noise and friction performance to that of conventional cages made from polyamide 66. Alongside its potential to help OEMs develop carbon-neutral products, the new bioplastic cage demonstrates equivalent strength, heat resistance, grease resistance and weld strength to that of polyamide 66, as well as comparable stiffness, fatigue resistance, creep resistance and impact resistance.